An approach to study dynamic stability of pile-supported structures in liquefiable soils

Bhattacharya, S., Alexander N. A., and Adhikari, S.
6th International Conference on Urban Earthquake Engineering, Tokyo, Japan, March 2009.

Collapse and/or severe damage of pile-supported structures are still observed after strong earthquakes despite the fact that a large factor of safety against axial capacity and bending due to lateral loads is employed in their design. A recent investigation has conclusively shown that a pile may become laterally unsupported in the liquefiable zone during strong shaking and due to the axial load acting on it. This led to another failure mechanism: Buckling instability. Also, during seismic liquefaction, the axial load on the pile in the liquefied zone increases due to the loss of shaft resistance. Due to this extra axial load, the stiffness of the pile-soil system reduces and so does the first natural vibration frequencies. This paper aims to show that at the point of instability the fundamental vibration mode and buckling mode shapes are identical. A method is shown to analyse dynamic stability of piles in liquefiable soils.
BiBTeX Entry
@INPROCEEDINGS{cp70,
    AUTHOR={S. Bhattacharya and N. A. Alexander  and  S. Adhikari},
    TITLE={An approach to study dynamic stability of pile-supported structures in liquefiable soils},
    BOOKTITLE={6th International Conference on Urban Earthquake Engineering},
    YEAR={2009},
    Address={Tokyo, Japan},
    Month={March}
}
by Sondipon Adhikari